Input System

This page was rewritten on 2026-05-15 to reflect the engineering reality surfaced by the
architecture trace campaign. A prior version (added in commit 28bc94f21,
2025-09-08, by an automated documentation pass) described `InputSystem`, `InputConfig`,
`ActionMap`, `BindingRecorder`, `BindingProfile`, `ContextPriority`, `InputBuffer`,
`InputPredictor`, `InputRecorder` and a `mapping` / `rebinding` / `replay` / `buffer` /
`device` submodule layout. **None of those types or submodules exist** in
`astraweave-input/src/lib.rs` re-exports.

Actual public surface

astraweave-input is a pure facade over winit (window/keyboard/mouse events) and gilrs (gamepad). The lib.rs re-exports are:

• Action — high-level input action enum.
• Binding — single key/button/axis-to-action mapping.
• BindingSet — collection of bindings (load / save / merge).
• InputManager — runtime state, polls device events, drains an action queue.
• Axis2 — 2D axis value (gamepad sticks, mouse delta).

That is the complete external surface. There is no InputSystem, no InputConfig, no BindingRecorder, no InputBuffer, no InputPredictor, no InputRecorder.

Declared-but-unused dependency hazard

Two workspace crates declare astraweave-input as a Cargo dependency but never import it in any source file:

• astraweave-gameplay/Cargo.toml
• astraweave-ui/Cargo.toml

Verified by workspace-grep for use astraweave_input. The dep additions left no source-file imports in git history. This is documented in input.md §4 and §11 and tracked as Q21 in ARCHITECTURE_MAP.md §14.

The single in-tree consumer of astraweave-input is examples/ui_controls_demo, and even that demo does not read the InputManager state — it matches raw winit KeyCode directly.

Editor reinvents the input domain

The visual editor’s input-bindings panel (tools/aw_editor/src/panels/input_bindings_panel.rs, 2,511 LoC, 13 types) reimplements the entire input vocabulary in-place, without depending on astraweave-input. This is one of the four confirmed instances of the §7.7 wrapped-component resource identity trap surfaced by the Editor Multi-Tool Architecture campaign — the editor’s input layer and the engine’s input layer manage the same logical resource but neither delegates to the other.

Tracked as Q22 in ARCHITECTURE_MAP.md §14.

Silent-failure shape

load_bindings in astraweave-input/src/save.rs:16-19 collapses every error mode (file not found, parse error, schema mismatch) to None. Users get a default binding set with no diagnostic indication of what failed.

Where to actually look in the code

Further reading

• input.md — full input-system trace (file map, conflict map, decision log, invariants, open questions).
• ARCHITECTURE_MAP.md §2.3 (anomaly 8), §7.1, §14 (Q21, Q22).
• Interactive workspace map — select astraweave-input to see the declared-but-unused dependency edges from astraweave-gameplay and astraweave-ui rendered as dashed/tee-terminated lines.